透平叶片在气热固耦合场下的热变形分析
Analysis of the Thermal Deformation of Turbine Blade Coupling Gas-heat-solid Field

叶片尺寸对涡轮机的工作效率影响很大，为了研究透平叶片在复杂工况下的热变形，建立了气-热-固耦合模型。通过改变冷却工质比，获得一系列的三维温度场和热变形分布。结果表明：叶片的热变形整体表现为从压力面向吸力面弯曲，纵向热膨胀显著，横向的变形较小，最大变形位于叶顶前缘。随着叶片表面温度降低，热变形对温度敏感度变差。在高温段可用纵向变形来近似代替叶片总变形。该模型可预测叶片热变形，为叶片尺寸设计和型面尺寸校正提供参考数据。
Blade size can greatly influence the work efficiency of turbine. In order to analyze heat deformation of turbine blades under complex working conditions, a model coupling gas-heat-solid field was established to simulate the three dimensional flow fields. The temperature distribution and the corresponding deformation caused by thermal effect were acquired by changing the flow ratio between main stream and coolant. The results show that the deformation as a whole characterize as bending from the pressure side to suction side, and wich in vertical direction are much larger than that in horizontal direction. The largest deformation locates in the leading edge of blade tip. The thermal deformation is less sensitive with the decreasing of surface temperature. The thermal deformation can be approximately estimated by the vertical one. The present model can predict the thermal deformation of blade and provide the deformation for design and modify the blade dimensions